Proper placement of components during total knee arthroplasty is critical to obtaining excellent results and avoiding complications. The process of preparation of the bone to accept an implant involves removing the appropriate amount of bone in the proper shape, position, and size for the appropriate implant. Natural knees “come” in an infinite number of different shapes and sizes, while artificial implants, like shoes, may be made only in discrete sizes. A surgeon should select the best fit and place that implant properly and safely.